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1.
In 1929, V. F. Brotherus published eight species and one form of Chinese Brachytheciaceae based on Handel-Mazzetti's collections from Hunan, Guizhou and Yunnan provinces of China during 1914~1918. The holotypes of all the taxa mentioned above were studied by the present authors. Three names are newly reduced to synonyms: Brachythecium subcurvatulum≡ Brachythecium velutinum ; Rhynchostegium gracilescens≡ Eu-rhynchium savatieri and Rhynchostegium obsoletinerve≡Herzogiella turfacea.  相似文献   

2.
(1) The systematic positions of Clematis potaninii Maxim., C . heynei Rau, C. trichotoma Nakai, C. apiculata Hook. f. & Thoms, C. theobromina Dunn, C. sigensis Engler,C. hedysarifolia DC., and C. dissecta Baker, and the specific status of C. trifida Hook, C.pimpinellifolia Hook., C. oligophylla Hook., and Clematopsis lineariloba Hutch. are discussed; (2) New classifications for Clematis parviloba Gardn. & Champ., C. puberula Hook. f. & Thoms., and sect. Naraveliopsis Hand.-Mazz. are provided; (3) Clematis subsect. Potaninianae M. Johnson, C. heynei M. Johnson, C. petelotii Gagnep. and some other names are reduced to synonymy; (4) Two subsections, 4 series, 4 species, and 4 varieties are described as new; (5)Four new ranks and 4 new combinations are made.  相似文献   

3.
(1) Clematis taiwaniana Hayata, C. grata Wall. var. ryukiuensis Tamura, C . sikkimensis (Hook. f. & Thoms. ) Drumm. ex Burkill, C. connata DC. var. bipinnata M. Y. Fang, C. kilungensis W. T. Wang & M. Y. Fang etc. are reduced to synonymy. (2) New classifications for sect. Tubulosae Decne., C. siamensis Drumm. & Craib and C. connata DC. are proposed. (3) 3 series, 3 species and 4 varieties are described as new. (4) 6 new combinations and 3 newranks are made.  相似文献   

4.
( 1 ) Some taxonomical problems of the genus Clematis mainly about misidentifications are discussed, and some treatments including the reinstatement of Clematis montana var. brevifoliola Kuntze, C. apiifolia var. biternata Makino, C. subumbellata Kurz, C. goudotiana Planch. & Triana, C. insidiosa Baill., C. kockiana Schneid. and C. longicauda A. Rich., and the reduction of subsect. Africanae M. Johnson, C. umbellifera Gagnep., C. pubescens Benth., C. rhodocarpa Rose, C. edentata Baker, C. stoltzi Engler, C. tibetana ssp. vernayi var. dentata Grey-Wilson, C. clarkeana var. stenophylla Hand.-Mazz., C. subfalcata Pei ex M.Y. Fang, C. angustifoliola W. T. Wang, C. dasyandra var. polyantha Finet & Gagnep. etc are given. (2) The new diagnoses for the two subsections of the sect. Meclatis are provided; C. sericea H.B. K. ex DC. and C. grossa Benth. are treated as two varieties of one species; and a new classification of the infraspecific taxa of C. hirsuta Perr & Guill. is made. (3) one subsection, one series, eight species and one variety are described as new. (4) The new occurrences of C. montana var. brevifoliola Kuntze in southern Xizang, China, Nepal, Bhutan and northern Myanmar, C. burmanica Lace in southwestern Yunnan, C. armandii Franch. in Assam, India and northern Myanmar,and C. yui W. T. Wang in northern Myanmar are reported.  相似文献   

5.
(1) The evolutionary trends of sepals and stamens of the genus Clematis are discussed; (2) New classifications for sect. Cheiropsis DC. and sect. Aspidanthera Spach are proposed; (3) One subsection, 13 series, 5 species and 4 varieties are described as new; (4) Six new ranks and2 new combinations are made.  相似文献   

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8.
Summary Modification of liquefying -amylase by diethylpyrocarbonate or its photo-oxidation in the presence of rose bengal caused rapid loss of enzyme activity. The photo-oxidation followed pseudo-first-order kinetics giving maximal value at pH 8.0. The photo-oxidized enzyme showed a characteristic increase in absorbance at 250 nm which was directly proportional to the extent of inactivation. Diethylpyrocarbonate at low concentration at pH 6.0 and 30 ° C completely inactivated a-amylase. Inactivation followed pseudo-first-order kinetics. The reaction order with respect to inactivation by diethylpyrocarbonate was one, thus indicating modification of a single histidine per mole of the enzyme. Diethylpyrocarbonate-modified enzyme showed increased absorbance at 240 nm which was reversed completely upon treatment with NH2OH at 30 °C for 16 hr. Calculating the histidine residues being modified from the increase in absorbance at 240 nm showed that three residues were ethoxyformylated on treatment with diethylpyrocarbonate, of which only one was found at the active site. Substrate and competitive inhibitor protects the enzyme against both, photo-oxidation, and modification by diethylpyrocarbonate, confirming that histidine plays an essential role at the -amylase active site.  相似文献   

9.
Herbicides are the most successful weed control technology ever developed. To assess the effects of herbicides on non-target plants, a study was carried out by using Imazethapyr (IM) on JG-11 cultivar of chickpea germination and early growth. Hydroponic conditions with five concentrations (0.5, 1, 2.5, 5, and 10 ppm) of IM were employed along with control. On the termination day of germination, IM had no effect on the percentage of seed germination but a significant decrease in the length of radicle and plumule, speed of germination, vigour index, tolerance index, and pigment content was observed with an increase in concentration of the herbicide. Increase in phytotoxicity percent and mean germination time along with a marginal decrease in dry and fresh weight was seen with increasing IM dose. The results implied that a higher concentration of IM resulted in a decline in seed germination and early growth of non-target or main crop i.e. chickpea.  相似文献   

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11.
The advent of genomic and proteomic technologies in this post-genomic era has urged the researchers to develop novel research strategies against cancer by targeting the human genes that would greatly facilitate to identify more promising treatment and to develop accurate early diagnosis for cancer. To harness the power of cancer genetic information towards better treatment we have developed a cancer gene database called CanGeneBase (CGB). It is a comprehensive data collection of cancer-related genes with the intention of helping the researchers to stay on a single platform to gain exclusive information on the genes of their interest. According to the Cancer Gene Data Curation Project, about 4,700 genes have been identified as being related to cancer. The present CanGeneBase covers about 12 different types of cancer which includes 190 unique gene entries. Each entry encompasses about 33 useful parameters to provide detailed information about specific gene. CanGeneBase is made in such a way that it can be easily accessed by either gene symbol or by the type of cancer.

Availability

The database is freely available at http://122.165.25.137/bioinfo/cancerdb/  相似文献   

12.
采用冷渗漉提取的方法提取马兰的化学成分.经硅胶柱色谱和Sephadex LH-20进行分离纯化,通过理化方法和波谱数据分析进行结构鉴定.从80%乙醇冷渗漉提取物的水不溶物中分离并鉴定了12个化合物,分别为正十六烷酸(1)、6-羟基-桉烷-4(14)-烯(2)、β-谷甾醇(3)、α-菠菜甾醇(4)、香草醛(5)、β-20(21),24-二烯-达玛烷-3-酮(6)、豆甾醇(7)、木栓酮(8)、羽扇豆酮(9)、α-香树脂醇(10)、表木栓醇(11)、神经酰胺(12).化合物2、6、9、12均为首次从该种植物中分得.  相似文献   

13.
Biodegradable molecularly imprinted polymers based on poly(ε-caprolactone)   总被引:1,自引:0,他引:1  
Novel biodegradable molecularly imprinted polymers (MIPs) based on poly(ε-caprolactone) (PCL) were prepared by combining two important properties required of ideal biomaterials, biodegradability (with biocompatibility) and molecular recognition properties. Acrylate or methacrylate end-capped PCL macromers were synthesized through the reaction of PCL diol or triol with acryloyl or methacryloyl chloride. The synthesis of acrylate or methacrylate end-capped macromers was confirmed using FT-IR and H NMR spectroscopic techniques. These macromers were used to prepare biodegradable crosslinked networks by photopolymerization with functional monomer (acrylic acid) and a model template (theophylline). The theophylline-imprinted polymer showed higher binding capacity for theophylline compared with non-imprinted polymer (NIP), and also showed selectivity for theophylline over caffeine (similar structure molecules). PCL-based MIP degraded 8% of the initial weight in 30 days in phosphate-buffered saline (PBS) solution (pH 7.4) and over 90% of the initial weight within 24 h in 1 N NaOH at 37°C.  相似文献   

14.
Since 1988s, the phenomenon of multiple seedlings and multiple embryoes of apomictic rice, Ap Ⅲ (Shuang 13) has been interestingly concerned. Embryological investigation of Ap Ⅲ has been carried out with the whole dissection and conventional sectioning technique. The main conclusions are as follows: 1.8. 9 % of 5000 matured caryopsises, contained one embryo in a caryopsis, from which single seedling arose, while 8.9 % twin embryoes and 1.2 % triplet embryoes of which developed two seedlings and triple seedlings respectively; 2. In over 700 young caryopsises, 90.0%~95.0% contained only one embryo, 5.0%~7.0% twin embryoes, except a few of the ovules with absorptive embryo sac or embryo and endosperm. Triplet embryoes caryopsis could not be traced further due to their low frequency; 3. Authors' materials showed that all the single, twin and triplet embryoes were situated at the micropylar end in one embryo sac of young ovule and no adventitious embryo was seen outside the embryo sac of ovules. From the aforementioned results, it can be infered that albeit single embryo is derived from the egg cell yet it could be possible twin or triplet embryocs may be developed from the egg cell and one or two of the synergids either or not through fertilization.  相似文献   

15.
The present paper reports four new species of Chinese marine red algae belonging to Ahnfeltiales and Gigartinales. They are Ahnfeltia yinggehaiensis Xia et Zhang, Ahnfeltiopsis guangdongensis Xia et Zhang, Ahnfeltiopsis hainanensis Xia et Zhang, Ahnfeltiopsis masudai Xia et Zhang. Key words Ahnfeltia;A.yinggehaiensis;Ahnfeltiopsis;A.guangdongensis;A.hainanensis;A.masudai;Hainan;Guangdong;New species  相似文献   

16.

From 1994 to 1997 investigations have been carried out on fields of the "Ökohof Seeben" in Halle (Saale), refering to long-term effects of ecological agriculture on fauna, flora and soil. For the sampling of the epigeic fauna, pitfall traps were used. The purpose was to examine the effect of the changes in management on spiders for example. The influence of field size, edge-structures and different crops on species- and individual-numbers was studied. The question was, whether ecological agriculture results in an increasing biodiversity overviewed over years. In 4 years, on 6 fields, 190 species of spiders (82,202 adults spiders) could be proved, among them 32 species endangered in Sachsen-Anhalt and 28 species endangered according to the Red-Data-Books of Germany. The species numbers in the edge-biotops were nearly twice the numbers in the fields. The activity density of pioneer species (for example Oedothorax apicatus ) decreased rapidly on all fields. As a whole species numbers, and also the number of seldom species, were higher on the small fields than on the large fields lying in a poor structured environment. On the large fields some species, especially some Gnaphosidae and Lycosidae were missing in the first two years, but could be proved in the later years. Increasing numbers of species bigger in size and also more balanced dominance structures could be observed in the later years of investigation. In the fields the Linyphiidae species O. apicatus, E. atra, E. dentipalpis, M. rurestris, L. tenuis, P. microphthalmum, A. humilis and the Lycosidae P. agrestis and P. prativaga were dominant. Other species, like D. concolor, B. gracilis, H. signifer, P. juncea, T. ruricola, D. pusillus, X. kochi, O. claveata, P. degeeri, P. palustris, R. lividus prefered the adjacent boundaries, but were represented in the field as well. Several species, such as A. cuneata, A. pulverulenta, T. terricola, X. miniata, X. nemoralis, A. albimana, P. mirabilis, Ch. campestre, X. acerbus, Z. spinimana, P. festivus, D. praeficus and D. lutetianus could be proved only in the adjacent boundaries. Altogether positive effects on the dominance structure of spiders could be shown. An increasing biodiversity may be expected.  相似文献   

17.
Summary Lymphapheresis was performed on a patient with Sézary syndrome. The Sézary cells were purified by removing E-rosette-forming and Fc receptor-bearing cells. Antiserum against these purified Sézary cells was raised in rabbits. This antiserum had cytotoxicity against Sézary cells as well as against normal peripheral blood lymphocytes. Absorption was carried out with chronic lymphocytic leukemia (CLL) and normal lymphocytes. The absorbed antiserum maintained cytotoxicity against Sézary cells but lost cytotoxicity against CLL and normal peripheral blood lymphocytes.Indirect immunofluorescence assay showed that the antiserum reacted against purified Sézary cells and a high percentage (66%) of peripheral blood mononuclear cells from five patients with Sézary syndrome. It also reacted against 5.7% of normal lymphocytes, 8% of CLL cells, 5% of the lymphocytes from a patient who had undergone splenectomy, 2% of lymphocytes from a patient with multiple myeloma, 5% of lymphocytes from a hairy cell leukemia patient, and 1% of acute lymphocytic leukemia cells (T cell). The antiserum did not react against thymocytes but reacted against 34.6% of the bone marrow lymphocytes. This unique marker was designated as sigma () antigen. It was suggested that Sézary syndrome may represent proliferation or malignant transformation of normally present antigen-positive lymphocytes.  相似文献   

18.
From January 2010 to December 2011, a total of 138 cases of ticks feeding on humans were reported from 11 locations in central Panama. Five of these locations were situated in forest environments, three in rural landscapes and three in urban areas. The ticks were submitted to the Gorgas Memorial Institute, where nine species were identified among 65 specimens: Amblyomma cajennense s.l., A. dissimile, A. naponense, A. oblongoguttatum, A. ovale, A. sabanerae, A. tapirellum, Haemaphysalis juxtakochi and Rhipicephalus sanguineus s.l. The remaining 73 specimens consisted of unidentified immature ticks, all belonging to the genus of Amblyomma. Rhipicephalus sanguineus s.l. was the species most frequently associated with humans, particularly in urban environments. In rural landscapes, tick bites were most often caused by A. cajennense s.l., whereas A. tapirellum was the species most often found parasitizing humans in forest environments. These data provide information on the tick species most commonly associated with humans in forested environments, rural areas and cities around the Panama Canal.  相似文献   

19.
In a search for thermophilic ethanol-tolerant bacteria, water-sediment samples collected at springs in Yunnan province of China were screened by ethanol enrichment. A novel thermophilic bacterium, strain E13(T) , was isolated. It exhibits a unique and remarkable ability to preferably grow in the presence of ethanol and is able to tolerate 13% (v/v) ethanol at 60 °C. The isolate is a facultative aerobic, Gram-positive, motile, spore-forming rod that is capable of utilizing a range of carbon sources, such as xylose, arabinose and cellobiose. Phylogenetic analysis based on 16S rRNA gene similarity showed the strain to be affiliated with the species Anoxybacillus flavithermus (99.2% sequence similarity). DNA-DNA hybridization comparisons demonstrated a 64.8% DNA-DNA relatedness between strain E13(T) and A. flavithermus DSM 2641(T) . On the basis of phenotypic characteristics, phylogenetic data and DNA-DNA hybridization data, it was concluded that the isolate merited classification as a novel subspecies of A. flavithermus, for which the name Anoxybacillus flavithermus ssp. yunnanensis ssp. nov. is proposed. The type strain of this subspecies is E13(T) (=CCTCC AB2010187(T) =KCTC 13759(T) ).  相似文献   

20.
We studied and modeled damage caused by Helicoverpa armigera larvae on cotton with the aim of developing a coupled crop pest model. Two damage components were studied: the voracity (quantity of fresh matter and number of organs consumed) and feeding preferences (type of organ infested). The laboratory no-choice study of voracity on excised squares and bolls revealed that an H. armigera larva consumes 2,856 mg of fresh matter throughout its larval life, with the sixth instar consuming 86% of this quantity. This consumption rate corresponded to 23.6 squares, or 7.8 bolls. We developed equations to predict the quantity of fresh matter uptake from an individual plant organ, according to the organ mass and the larval instar. The field study of feeding preference confirmed previous findings that larvae prefer squares to bolls, with this preference decreasing as the larval age increases. However, no significant relationship was noted between the age of larvae and the size of infested organs within each organ class (square or boll). We developed a logistic model to predict the probability of a larva infesting a boll rather than a square. According to this model, the relative organ availability in the field and the larval instar were found to be significant factors.  相似文献   

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